The present invention is directed toward a cultivating or weeding tool and more particularly toward such a tool which has a movable fulcrum member for adjusting the mechanical advantage of the tool.
Hand-operated cultivating tools and weeders have been known and used for many years by both farmers and home gardeners alike. These tools are comprised essentially of an elongated shaft or handle having a grip at one end thereof. Attached to the other end of the elongated shaft are a plurality of fork-like tines or similarly shaped elements. The tool is utilized by forcing the tines downwardly into the ground and then pushing the handle backwardly. The upper part of the tines or lower portion of the handle acts as a fulcrum or pivot point about which the tool rotates. As the handle is pushed downwardly, the tines move upwardly breaking up the ground and lifting weeds or the like therewith.
It has been proposed in the past to increase the pivoting effect of cultivating and similar tools by adding a fulcrum member behind the upper part of the tines. One such proposal is shown, for example, in U.S. Pat. No. 1,494,557 which shows a tubularly shaped fulcrum member welded to a fixed point behind the tines. U.S. Pat. No. 567,391 shows a similar device but which is in the shape of a cylinder mounted for rotation.
While these prior art devices may have had limited advantages, they are not applicable to all types of cultivating and weeding tools and are relatively difficult to construct since they require a welding process. Furthermore, the pivot point is fixed and cannot be adjusted if desired.
U.S. Pat. No. 1,142,783 shows an arrangement which is substantially simpler to construct than the arrangements of the patents discussed above. This device includes a metal plate having two holes therein through which the tines of the tool can pass. An elongated piece of sheet metal extends from the plate and is bent into a U, the free end of which contacts the rear surface of the handle. While this device is relatively simple and inexpensive, it suffers from the same drawbacks of the first two patents mentioned above in that the pivot point or fulcrum cannot be adjusted.